Shape-memory polymer foam device for treating aneurysms

Abstract

A system for treating an aneurysm in a blood vessel or vein, wherein the aneurysm has a dome, an interior, and a neck. The system includes a shape memory polymer foam in the interior of the aneurysm between the dome and the neck. The shape memory polymer foam has pores that include a first multiplicity of pores having a first pore size and a second multiplicity of pores having a second pore size. The second pore size is larger than said first pore size. The first multiplicity of pores are located in the neck of the aneurysm. The second multiplicity of pores are located in the dome of the aneurysm.

The invention claimed is: 
     
       1. An apparatus to treat an aneurysm in a blood vessel, wherein the aneurysm has a dome, an interior, and a neck; comprising:
 a shape memory polymer foam to be boated in the interior of the aneurysm between the dome and the neck; and 
 at least one fluid transport channel that includes: a first portion in a first peripheral wall of the shape memory polymer foam, a second portion in a second peripheral wall of the shape memory polymer foam, and a third portion that couples the first and second portions to each other; 
 wherein said shape memory polymer foam has pores that include a first multiplicity of pores having a first pore size and a second multiplicity of pores having a second pore size, said second pore size being larger than said first pore size; 
 wherein said first multiplicity of pores having a first pore size are configured to be located in the neck of the aneurysm; 
 wherein the third portion includes at least one of the first and second multiplicities of pores. 
 
     
     
       2. The apparatus of  claim 1  wherein said second multiplicity of pores having a second pore size are configured to be located in the dome of the aneurysm. 
     
     
       3. The apparatus of  claim 1  further comprising additional multiplicities of pores in said shape memory polymer foam, wherein said additional multiplicities of pores have pore sizes larger than said first pore size but smaller than said second pore size. 
     
     
       4. The apparatus of  claim 3  wherein said first multiplicity of pores, said additional multiplicities of pores, and said second multiplicity of pores are configured to be located in the interior of the aneurysm with a gradation of pore size wherein the pores with the smallest pore size are configured to be in the neck of the aneurysm and the pores with the largest pore size are configured to be in the dome of the aneurysm. 
     
     
       5. The apparatus of  claim 1  wherein said shape memory polymer foam comprises separate pieces of shape memory polymer foam with differing pore sizes to be located in the interior of the aneurysm between the dome and the neck. 
     
     
       6. The apparatus of  claim 5  wherein the separate pieces of shape memory polymer foam are not monolithic with each other. 
     
     
       7. The apparatus of  claim 1  wherein said shape memory polymer foam comprises a shape memory polymer foam unit with differing pore sizes to be located in the interior of the aneurysm between the dome and the neck, said shape memory polymer foam unit having a base configured to be located in the neck of the aneurysm, and further comprising a coating of non-porous shape memory polymer on said base of the foam unit. 
     
     
       8. The apparatus of  claim 1  further comprising an array of non-porous baffles in said shape memory polymer foam to be located in the interior of the aneurysm between the dome and the neck; wherein the baffles are located between walls of the shape memory polymer foam. 
     
     
       9. The apparatus of  claim 1  further comprising a wire backbone, wherein said shape memory polymer foam comprises a series of shape memory polymer foam pieces that are distributed along said wire backbone. 
     
     
       10. The apparatus of  claim 1  further comprising a wire backbone, wherein said shape memory polymer foam comprises a single monolithic shape memory polymer foam unit located on said wire backbone. 
     
     
       11. The apparatus of  claim 1  wherein said shape memory polymer foam comprises a shape memory polymer foam unit with differing pore sizes to be located in the interior of the aneurysm between the dome and the neck, said shape memory polymer foam unit having a base configured to be located in the neck of the aneurysm, further comprising a coating of non-porous shape memory polymer on said base of the foam unit and further comprising a void in the interior of the aneurysm, wherein said void is located in the dome of the aneurysm. 
     
     
       12. The apparatus of  claim 1 , wherein:
 a single axis intersects the second multiplicity of pores, the first and second peripheral walls of the shape memory polymer foam, and a middle portion of the shape memory polymer foam that couples the first and second peripheral walls to each other; and 
 the second multiplicity of pores extend from the first peripheral wall all the way through the middle portion of the shape memory polymer and all the way to the second peripheral wall. 
 
     
     
       13. The apparatus of  claim 1  wherein the shape memory polymer foam has a peripheral wall that includes dimples.